In related art, a topological structure represents how devices, such as a server and a switch, in a network are coupled to one another. In the case where it is possible for each of multiple transmission sources to communicate with any of multiple destinations via a topological structure, the topological structure may be called a topological structure allowing communication from all to all (All-to-All communication). Furthermore, there is a topological structure that allows all-to-all communication without path conflict.
In related art, for instance, there is a technique including a first network coupled to multiple nodes and switches, and a second network partially coupled to the multiple nodes. Also, a program task has hierarchical level In, and may be connected by an interconnection network using a hierarchical network topology where N>1, n=1 to N.
Related techniques are disclosed in, for example, Japanese Laid-open Patent Publication Nos. 2009-020797 and 2014-164756.